摘要
本文利用区域布格重力异常图(1:100万)和地质构造资料来研究河北省南部及其相邻地区的地壳深部构造特征,并讨论其与强震发生的关系。方法主要是运用三维重力正演计算,层层消除地壳浅部对布格重力异常的影响,得出一系列剩余重力异常和剩余深部重力异常,再根据异常图形的变换,探讨一些活动断裂和构造由浅到深的变化趋势。还用三维重力反演计算,求出了全区莫霍界面的深度,得到了全区的地壳厚度图,进而分析强震区的深部构造背景,这些对地震地质和烈度区划是有意义的。
In this paper, the characteristics of the deep erustal structures in South Hebei province and its adjacent area and its relationship to the strong earthquakes were sfudied by the use of the regional gravity data, e. g. the Bouguer Anomaly, Map (1: 1000000)and the geological information. The main method used are: 1). utilizing 3-D normal gravitional calculation to remove the influence resulted from the shallow crust layer by layer, a series of the residual gravity anomalies and the deep residual gravity anomalies were tained. The authors had made the analysis for the trend of some active faults and structures in the different depth based upon the transform of the anomalies patterns. 2). Thedepth of Moho surface was inversed and the map of the crustal thickness of the whole region was obtained. The deep crustal tectonic back-ground of the strong earthquake area was analysed and studied on the basis of the above results. The region which should be observed by some precursory methods were finally outlined. This may have interest with the study of seismogeology and the seismic intensity zonation.
出处
《华北地震科学》
北大核心
1990年第3期1-10,共10页
North China Earthquake Sciences
